Lunchbox insert



FIG. 1 is a perspective view of the lunchbox insert showing my new design;

FIG. 2 is an exploded perspective view thereof;

FIG. 3 is a front elevational view thereof, the opposite side being a identical;

FIG. 4 is a side elevational view thereof, the opposite side being identical;

FIG. 5 is a top plan view thereof; and,

FIG. 6 is a bottom plan view thereof. 

The ornamental design for a lunchbox insert, as shown and described. 